A preservative is a naturally occurring or synthetically produced substance that is added to products such as foods, pharmaceuticals, paints, biological samples, wood, etc. to prevent decomposition by microbial growth or by undesirable chemical changes. Preservatives can be divided into two types, depending on their origin. Class I preservatives refers to those preservatives which are naturally occurring, everyday substances. Examples include salt, honey and wood smoke.[1] Class II preservatives refer to preservatives which are synthetically manufactured.[1] Contents

Preservatives in foods[edit source | editbeta]Preservatives are often added to food to prevent their spoilage, or to retain their nutritional value and/or flavor for a longer period. The basic approach is to eliminate microorganisms from the food and prevent their regrowth. This is achieved by methods such as a high concentration of salt, or reducing the water content. This inhibits spoilage of the food item by microbial growth. Preservatives may be antimicrobial preservatives, which inhibit the growth of bacteria or fungi, including mold or they can be antioxidants such as oxygen absorbers, which inhibit the oxidation of food constituents. Common antimicrobial preservatives include sorbic acid and its salts, benzoic...

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...Introduction
A preservative is a naturally occurring or synthetically produced substance that is added to products such as foods, pharmaceuticals, paints, biological samples, wood, etc. to prevent decomposition by microbial growth or by undesirable chemical changes. All food products except for the one growing in our kitchen garden have foodpreservatives in them. Every manufacturer adds foodpreservatives to the food during processing. The purpose is generally to avoid spoilage during the transportation time.
Food is very important for the survival, so food preservation is one of the oldest techniques used by human beings to avoid its spoilage. Different ways and means have been found and improved for the purpose. Boiling, freezing &amp; refrigeration, pasteurizing, dehydrating, pickling are the few traditional ways. Sugar, mineral salt and salt are also often used as foodpreservatives. Nuclear radiation is also being used now as foodpreservatives. Modified packaging techniques like vacuum packing and hypobaric packing also work as foodpreservatives. Preservativefood additives can be used alone or in conjunction with other methods of food preservation. Preservatives may be antimicrobial...

...“ FoodPreservatives”
Submitted in Partial Fullfillment
of the Requirements for the subject of
Advance Chemistry IV
to the
Pisco Private School
By:
Mary Maren M. Guanlao
4th year Blaise Pascal
Mary Maren M. Guanlao
Mrs. Maria Dulce Bongon
Adv Chemistry IV
12, April 2013
FoodPreservativesFood is all around us and is necessary for everyday survival. Yet it has become so different from what it used to be. With the developing of new technologies, transportation and a growing population we require food to last longer. Have you ever wondered why maybe the apple you eat is so deeply colored red, or perhaps why the food in chain restaurants manage to produce so much food, yet have it all taste the same? Many people don’t consider this, they put trust into food producers and marketers to tell them the truth and serve up healthy and safe food. Yet this is not the truth, food which was once a necessity is now a business. Yet what are the health dangers of these new “brands” of food, and what will the future hold for food? And how is the use of foodpreservatives affects this all?
What is FoodPreservatives? Preservation usually involves...

...﻿Food additives are substances that are added to the food. They serve as different functions such as preservation, flavorings and colorings, antioxidants, and stabilisers. They are added in the manufacture process intentionally or unintentionally. There are many different food additives, and they can be classified as natural or artificial.
Most food additives are naturally occurring, and some may even be beneficial. The common natural food additives such as citrus acid and ascorbic acid, for example, are categorized as foodpreservatives because they work on enzymes and disrupt their metabolism, which leads to the preservation.1 Foodpreservatives are very useful. It extends the shelf life of food items, which enables it to be stored for a period of time and not having to be consumed right away. However, due to its function, it might harm the friendly bacteria that can cause digestion problems, and etc.2 Food additives are also used to enhance the flavor or the color of the food item. This is to add the taste and visual appeal of the food. They include caramel, curcumin, and etc. These are made from natural ingredients such as sugar and turmeric. They are safe to consume. However, some artificial colorings such as amaranth or red 2G have been banned because it was said to may cause cancer....

...﻿DELHI PUBLIC SCHOOL
DAGAPUR , SILIGURI
(Affiliated to C.B.S.E.)
Session :- 2012-13
Topic :
Study of effect of Potassium bisulphite as a foodpreservative
Submitted To: Submitted By:
Mr. B.GHOSH
H.O.D. Chemistry 12th Science
Roll no. =
Certificate
This is to certify that s/o Mr. Amar Singh is a bonafide student of class XIIth Science during session 2012-2013. He has completed his project on Study of effect of Potassium bisulphite as a foodpreservative successfully under my guidance and supervision.
Mr. S.P. DAS Mr. B.GHOSH
(Head of the institution) (H.O.D. Chemistry)
Acknowledgement
Acknowledgement is the most beautiful page in any project’s final pages. More than a formality, this appears to me the best opportunity to express my gratitude.
My project can never begin without you, dear GOD. Rather than saying “thank you” to you, you know that I feel like saying ‘I love you’, to you, always.
I must say thanks to my parents who provide me sufficient money and help in making of this project.
Mr. B.GHOSH , you are real foundation of the project done by me. My project would never have been possible without your guidance. Thank you very much.
Special thanks to my principal who gave support to me and library which provides me helpful books related to this project.
Next on my thanks lists are my friends, teachers, students who really...

...INTRODUCTION
The use of food additives is an emotional topic which continues to provoke consumer concern. Despite modern-day associations food additives have been used for centuries. Food preservation began when man first learned to safeguard food from one harvest to the next and by the salting and smoking of meat and fish. The Egyptians used colors and flavorings, and the Romans used saltpeter (potassium nitrate), spices and colors for preservation and to improve the appearance of foods. Cooks regularly used baking powder as a raising agent, thickeners for sauces and gravies, and colors, such as cochineal, to transform good-quality raw materials into foods that were safe, wholesome and enjoyable to eat. The overall aims of traditional home cooking remain the same as those prepared and preserved by today's food manufacturing methods.
Over the last 50 years, developments in food science and technology have led to the discovery of many new substances that can fulfill numerous functions in foods. These food additives are now readily available and include; emulsifiers in margarine, sweeteners in low-calorie products and a wider range of preservatives and antioxidants which slow product spoilage and rancidity whilst maintaining taste.
A food additive is defined as "any substance not normally consumed as a...

...Food Additives: Pros, Cons, and Some Ideas For The Future
America and indeed much of the world lives off of foodstuffs to which substances have been added to achieve some desired effect. In many ways it is the by-product of industrialization, rapidly expanding populations, technological advances, and changing consumer demand and expectations. It is now an undisputed fact that the foods which we eat on a daily basis are largely processed. By processed, in our contemporary day and age we refer not only to simple changes applied to the food with commonly found natural substances as in the pre-industrial era, but to more complexly engineered changes developed from the designs of food scientists in far-off labs. On the whole, there is a very significant amount of processing done to our food between the points at which it is taken from nature as an ingredient, to the point that it reaches our mouths at the table. There are literally thousands of various additives which have been discovered and developed to alter our food. (Wikipedia, “Food additives). How then is it that we take this processing for granted? Why do we ignore such great alterations to the very stuff which we rely on for nourishment and survival? It is largely because of the fact that much of the alterations made to our food are invisible to us as well as the fact that most Americans have been...